Packaging with a subsequently molded form-fit connection

ABSTRACT

The present invention relates to a packaging with a packaging trough, into which a packaging material can be filled and which is closed with a lid, whereby at least one form-fit connection connects the packaging trough with the lid and the connection comprises a first and a second connector.

This application claims benefit of Ser. No. 11/609,637, filed on Dec.16, 2006, which is a Continuation-in-part and claims benefit from U.S.patent application Ser. No. 11/181,037, filed on Jul. 13, 2005, now U.S.Pat. No. 7,665,281, which claims the benefit of InternationalApplication No. PCT/EP2004/003413, International Filing Date, Mar. 31,2004, which designated the United States of America, and whichinternational application was published under PCT Article 21 (2) as No.WO 2004/089583 A3 and which claims priority from German Application No.10316303.4, filed Apr. 8, 2003.

The present invention relates to a packaging with a packaging trough,into which a packaging material can be filled and which is closed with alid, whereby at least one form-fit connection connects the packagingtrough with the lid and the connection comprises a first and a secondconnection means.

Items of packaging as a rule comprise a packaging trough, into which thepackaging material, for example foodstuff, can be filled. This packagingtrough is then closed with an, as a rule, preformed lid. In order toincrease the pull-off force of the lid from the packaging trough afterthe initial opening, it is advantageous for the re-closure capability ifat least one form-fit connection is present between the lid and thepackaging trough. This form-fit connection comprises two connectionelements, for example a groove and a tongue, whereby the tongue isintroduced into the groove.

At present, the connection elements are molded into the lid and into thepackaging trough during deep-drawing. Since the lid and the packagingtrough must, however, be able to be removed again from the respectivedeep-drawing die after deep-drawing and one connection element must beable to be introduced into the other, the shape of the connectionelements is very greatly restricted.

The problem of the present invention, therefore, was to make available apackaging that does not display the drawbacks of the prior art.

This problem is solved with a packaging with a packaging trough, intowhich a packaging material can be filled and which is closed with a lid,whereby at least one form-fit connection connects the packaging troughwith the lid and the connection comprises a first and a secondconnection element, wherein at least one connection element has beenmolded at least partially into the packaging after the packaging troughhas been closed with the lid.

It was extremely surprising for the expert and not to be expected thatthe packaging according to the invention can have an arbitrarily shapedform-fit connection between the lid and the packaging trough. Very greatdesign possibilities of the form-fit connection between the packagingtrough and the lid thus arise, so that the force that is required toremove the lid from the packaging trough can for example be adjustedvery exactly. The packaging according to the invention can be producedin a straightforward manner and cost effectively.

According to the invention, the packaging comprises a packaging trough,into which the packaging material can be filled, and a lid. Both thepackaging trough and the lid are preferably manufactured from a plasticsmaterial and are deep-drawn in each case. The plastic material may becomparatively stiff and/or foamed. At least one, but preferably several,form-fit connections are arranged between the lid and the packagingtrough, whereby the form-fit connection is brought about in such a waythat the force that is required to detach the lid from the packagingtrough is increased. The form-fit connections can be distributedarbitrarily over the circumference of the packaging. Furthermore, theform-fit connections can be combined with a joint, whereby at least oneform-fit connection is then arranged opposite the hinge (joint).Furthermore, the form-fit connections can also be used as snapconnections for the re-closure of the items of packaging. According tothe invention, the form-fit connection comprises a first and a secondconnection means, which engage into one another and thus bring about theform-fit connection. All connection elements familiar to the expert canbe considered as connection elements, with which it is possible toachieve a form closure between the packaging trough and the lid.Preferably, however, the connection element is a groove and tongueconnection or two spherical part-shells which engage into one another.The connection preferably extends parallel to the transport direction ofthe film web from which the packaging is produced.

According to the invention, the packaging has at least one, butpreferably two or more, form-fit connections.

The lid and the packaging trough are preferably sealed to one another inthe region of a sealing plane. This sealing is preferably peelable, sothat the packaging can be closed again by means of the form-fitconnection.

The connections are preferably inserted by thermal molds into thepackaging trough. The connection should preferably be inserted from theinside to the outside, i.e. the circumference of the packaging increasesin the region of the connection. The advantage of this design of thepresent invention is that the surface by which the goods can be removedfrom the packaging is not reduced by the inner moldings, or that noadditional outward bulges have to made into which the connections arethen shaped, as disclosed in EP 0 367 603 A2.

The inner molding is preferably located in the lateral walls of thepackaging trough.

The lid is preferably sealed to the packaging trough. This sealing ispreferably peelable so that the connection serves as a resealing deviceafter the packaging is opened for the first time. The lid is preferablysealed to the packaging trough along an essentially horizontal sealingplane.

The items of packaging may be arbitrarily shaped, but the items ofpackaging preferably have an essentially square or round base surface.

The invention will be explained below with the aid of FIGS. 1 to 2B.These explanations are merely by way of example and do not restrict thegeneral ideas of the invention. The explanations apply equally to allthe subject-matters of the present invention.

FIG. 1 shows the packaging according to the invention and

FIG. 2 shows two possible embodiments of the form-fit connection.

FIG. 1 shows the packaging according to the invention, which comprises apackaging trough 2 and a lid 3. A packaging material, for examplefoodstuff, can be placed into packaging trough 2. Packaging trough 2 isthen closed with lid 3. After the packaging trough has been closed withthe lid, form-fit connection 4 is molded into the lid and/or thepackaging trough. In the present case, the form-fit connection is moldedboth into lid 3 and into packaging trough 2. The packaging according tothe invention is produced on a packaging machine, whereby the packagingtrough and the lid are either placed as ready molded parts into thepackaging machine or are molded into a plane film web, for example bydeep-drawing. In each case, the items of packaging are transported,preferably cyclically, along the running direction represented by thearrow inside the packaging machine. The expert will recognize that, inthe present case, form-fit connection 4 is arranged parallel to therunning direction of the packaging machine. The lid and the packagingtrough are sealed to one another in a peelable manner in the region ofthe sealing plane before the form-fit connection has been molded intothe packaging.

FIG. 2A-B show two possible design shapes of the form-fit connection.FIG. 2A shows a groove tapering to a point, which extends into and outof the plane of the paper. Due to the fact that the form-fit connectionis molded into the lid and the packaging trough only after the lid hasbeen placed onto the packaging trough, it is possible to produce shapesof the form-fit connection which were not possible according to theprior art. For example, it was not possible to produce a groove andtongue in such a pointed fashion depicted in FIG. 2A, without the lattereither no longer being able to be removed from the mould or becomingdamaged during the fitting together of the lid and the packaging trough.

FIG. 2B represents a hemispherical design of the form-fit connection.The expert will understand that it is advantageous for several suchspherical form-fit connections to be arranged over the circumference ofthe packaging trough. Reference is further made to the commentsconcerning the embodiment according to FIG. 2A.

1. A packaging (1) with a packaging trough (2), into which a packagingmaterial can be filled and which is closed with a lid (3), whereby atleast one form-fit connection (4) connects the packaging trough (2) withthe lid (3) and the connection (4) comprises a first and a secondconnection element (4′, 4″), characterized in that at least oneconnection element (4′, 4″) has been molded at least partially into thepackaging (1) after the packaging trough (2) has been closed with thelid (3).
 2. The packaging according to claim 1, characterized in thatboth connection elements (4′, 4″) are molded into the packaging afterthe packaging trough (2) has been closed with the lid (3).
 3. Thepackaging according to claim 1, characterized in that the connectionelements are groove (4′) and tongue (4″).
 4. The packaging according toclaim 1, characterized in that the form closure increases the pull-offforce of the lid (3) from the packaging trough (2).
 5. The packagingaccording to claim 1, characterized in that the connection (4) isarranged parallel to the direction of transport of the items ofpackaging in a packaging machine.
 6. The packaging according to claim 1,characterized in that it has at least two form-fit connections (4). 7.The packaging according to claim 1, characterized in that the lid (3)and the packaging trough (2) are sealed to one another, preferably in apeelable manner.
 8. A method for producing a packaging (1) having apackaging trough (2) and a lid (3), whereby the packaging trough (2) isclosed with the lid (3), characterized in that a form-fit connection(4), which connects the lid with the packaging trough, is then moldedinto the packaging.
 9. The method according to claim 8, characterized inthat the connection (4) is molded into the packaging after the lid hasbeen sealed to the packaging trough.
 10. The method according to claim1, characterized in that the connections are preferably molded intransversely to the direction of conveying.
 11. The method according toclaim 1, characterized in that the connections are molded in with anembossing means which interacts with a counter-bearing (7), and in thatthe counter-bearing is rotated and lowered after molding in.
 12. Apackaging machine having embossing means (5, 6) with which at least oneconnection element (4′, 4″) can be molded into a packaging.
 13. Thepackaging machine according to claim 10, characterized in that theembossing means (5, 6) are mounted so as to be displaceable crosswise tothe direction of transport of the film web.
 14. The packaging machineaccording to claim 1, characterized in that the embossing means (5, 6)cooperate with counter-bearings (7).
 15. The packaging machine accordingto claim 1, characterized in that it has a sealing station and that theembossing means (5, 6) are downstream of the sealing station.
 16. Thepackaging machine according to claim 13, characterized in that thecounter-bearings (7) are arranged so that they are verticallydisplaceable.
 17. The packaging machine according to claim 13,characterized in that the counter-bearings (7) are rotabably mounted.18. The packaging machine according to claim 1, characterized in that ithas a sealing station and in that the embossing means (5, 6) arearranged after the sealing station.